Merge pull request #1626 from edmondchuc/feat/DefinedNamespaces-dir

Add __dir__ to DefinedNamespaceMeta.

rdflib/namespace/__init__.py

@@ -1,6 +1,6 @@
 import logging
 import warnings
-from typing import TYPE_CHECKING, List, Union
+from typing import TYPE_CHECKING, List, Union, Iterable
 from unicodedata import category
 
 from pathlib import Path
@@ -228,6 +228,10 @@ def __contains__(cls, item):
             if issubclass(c, DefinedNamespace)
         )
 
+    def __dir__(cls) -> Iterable[str]:
+        values = {cls[str(x)] for x in cls.__annotations__}
+        return values
+
 
 class DefinedNamespace(metaclass=DefinedNamespaceMeta):
     """

test/test_definednamespace_dir.py

@@ -0,0 +1,35 @@
+from rdflib import RDF
+
+
+def test_definednamespace_dir():
+    x = dir(RDF)
+
+    values = [
+        RDF.nil,
+        RDF.direction,
+        RDF.first,
+        RDF.language,
+        RDF.object,
+        RDF.predicate,
+        RDF.rest,
+        RDF.subject,
+        RDF.type,
+        RDF.value,
+        RDF.Alt,
+        RDF.Bag,
+        RDF.CompoundLiteral,
+        RDF.List,
+        RDF.Property,
+        RDF.Seq,
+        RDF.Statement,
+        RDF.HTML,
+        RDF.JSON,
+        RDF.PlainLiteral,
+        RDF.XMLLiteral,
+        RDF.langString,
+    ]
+
+    assert len(values) == len(x)
+
+    for value in values:
+        assert value in x